Pipe cutting device



Jan. 24, 1967 R, F'. ATKINSON 3,300,201

PIPE CUTTING DEVICE Filed 001,. 25, 1963 Figi Jan. 24, 1967 R. F. ATKINSON 3,300,201

PIPE CUTTING DEVICE Filed oct. 25, 1963 4 sheets-sheet 2 /mfeu r-aA Jan. 24, 1967 R. F. ATKINSON 3,300,201

PIPE CUTTING DEVICE Filed oct. 25, 196s 4 sheets-sheet :s

Jan. 24, 1967 R. F. ATKINSON PIPE CUTTING DEVICE 4 Sheets-Sheet 4 Filed 000. 25, 1965 United States PatentOiiFice Patented jan. 24, 1967 3,300,201 PIPE CUTTING DEVICE Robert F. Atkinson, Winnipeg, Manitoba, Canada, assignor, by direct and mesne assignments, to Plumbing & Heating Ltd., Winnipeg, Manitoba, Canada, a corporation of Canada Filed Oct. 25, 1963, Ser. No. 318,959 6 Claims. (Cl. 266-23) My invention relates to new and useful improvements in pipe or tube cutting machines.

The principle object and essence of this invention is to provide a pipe cutting machine which can cut off pipe or tubing irrespective of the diameter, within limits, and either at right angles or at an angle less than a right angle.

Another object of the invention is to provide a device of the character herewithin described which can make cuts in a pipe or tube the correct configuration for a saddle joint.

A still another object of the invention is to provide a device of the character herewithin described which is designed for easy transportation so that it can be used in the eld provided a source of electricity is available.

Still another object of the invention is to provide a device of the character herewithin described which is adaptable in use inasmuch as pipes of varying lengths and diameters can readily be cut thereby.

Still another object of the invention is to provide a device of the character herewithin described which is relatively simple in construction, economical in manufacture and otherwise well suited to the purpose for which it is designed.

With the foregoing objects in view, and such other objects and advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, my invention consists essentially in the arrangement and construction of parts all as hereinafter more particularly described, reference being had to the accompanying dr-awings in which:

FIGURE l is an isometric view of one embodiment of the device.

FIGURE 2 is a sectional view along the lines 2-2 of FIGURE 3.

FIGURE 3 is an enlarged fragmentary side elevation of one end of the device shown in FIGURE l.

FIGURE 4 is an enlarged fragmentary view substantially -along the line 4-4 of FIGURE 3.

FIGURE 5 is a side elevation of an alternative embodiment of the invention.

FIGURE 6 is a view along the line 6 6 of FIG- URE 5 but showing a belt drive connection between the pipe and the cutting torch assembly.

FIGURE 7 is a view substantially along the line 7 7 of FIGURE 5.

FIGURE 8 is a fragmentary end elevation showing one method of applying reverse direction to the lead screw mechanism.

In the drawings like characters of reference indicate `corresponding parts in the different figures.

Proceeding therefore to describe the invention in detail, FIGURES l to 4 inclusive show a device particularly suitable for use in the cutting of tubes or pipes at right angles and FIGURES 5 to 8 inclusive show a similar machine but including means to cut pipes at angles of less than 90 degrees for joining sections in order to make ya pipe angle.

Reference character 10 generally illustrates supporting framework comprising a pair of longitudinally extending members 11, vertical supports 12 and cross braces 13.

One lof the longitudinal members 11 together `with a longitudinally extending guide member 14 form a track along which a `cutting torch assembly collectively designated 15 may be moved slidably for positioning purposes.

A plurality of saddle members 16 span the longitudinal members 11 and are slidable therealong for adjustment purposes. These saddle members include arcuately curved upper surfaces 17 and it will be noted that these saddle members are comprised of a pair of spaced `and parallel side plates 18 and end plates 19.

The upper edges Iof said plates 18 are notched `as at 20 and these notches are adapted to receive the spindles 21 of carrying guide wheels 22 and it will be noted that there are a pair of guide wheels to each saddle assembly 16. By positioning these spindles 21 in the desired notches 20, the guide wheels can support varying diameters of pipe 23 which it is desired to cut.

It should also be noted at this point that -as these saddles are adjustable, they can be positioned so that both the main portion of the pipe 23 can be supported and also the portion that is cut therefrom.

Reference character 24 illustrates -a source of power such as an electric motor situated at one end of the supporting framework and supported by platform 25. This platform also includes a transmission box 26 and a speed reducing gear 27. In this connection it is desirable to have an electric motor 24 which is variable speed and reversible.l

The platform 25 is supported by two vertical rods 28 extending through cross brace 29 on the supporting framework and one of the rods is provided with a bevel gear 30 at the upper end thereof engageable by a further bevel gear 31 which in turn is rotatable by means of hand crank 32. A chain 33 extends around a pair ofv gears 34, one each of which is secured to the upper ends of the rods 28. It will therefore be appreciated that by rotating crank 32, the platform 25 is raised or lowered within limits and maintained in a level condition.

A pulley 33 is secure-d to the drive shaft 34 of the speed reducer 27 and a belt 35 extends around this pulley and around the perimeter of the pipe 23 which is supported for rotation upon the saddles 16.

It will therefore be appreciated that the source of power 24 rotates the pipe 23 upon the rollers 22.

When cutting pipe by means of the torch assembly 15, it is of course desirable that no endwise movement of the pipe occurs and in this connection reference should be made to FIGURES 3 and 4.

Vertical adjustable trunnions 36 mounted within bearing blocks'37 which in turn are supported between the longitudinals 11. lA'resiliently covered roller 38 is jour- 23 and then over the roller 38 as clearly shown in FIG- URE 3, Lthe direction of the belt runs being indicated by arrows 41 and 42. This causes the belt to pull the pipe endwise in the direction of arrow 43"and by careful adv justment of the roller.38, this pulling action is facilitated inasmuch as the roller 38 should be engaged in friction contact with the underside of the rotating pipe but not sufficient to lift the pipeclear of the rollers 22. Y

A thrust roller 43 is journalled within bearing 44 at one end of the supporting framework, hand crank 45 giving limited vertical adjustment of this roller. The rolle'r is adjusted so that it engages the end 46 of the pipe and the aforementioned belt together with the roller 38 maintains the pipe in contact with this thrust roller thus perventingl longitudinal movement of the pipe.

Referring back to the vertical adjustment of the source of power base 25, it will be appreciated that this enables one belt 35 to be used for a variety of pipe sizes.

A cutting torch assembly illustrated in FIGURE 1 is journalled for sliding movement upon the guide rails 14 and the adjacent longitudinal 11. It consists of a box like framework 47 upon which is mounted a torch table or platform 48. Adjustable arm 49 extending from the table holds a conventional cutting torch 50 and tubing 51 extends from the cutting torch to a solenoid assembly 52 and hence to a source of operating gas (not illustrated).

The solenoid assembly is of conventional design and enables the cutting ame to be adjusted by means of the conventional adjustors 53 on the torch and then to be extinguished and relit without changing the cutting characteristics. This solenoid assembly 52 operates valves within the lines extending to the source of supply.

Also mounted upon the platform 48 is a source of power 54 attached by means of flexible drive 55 to a grinding wheel 56 which may be used to dress the cut end of the pipe or to -cut desirable bevels upon the cut end as may be required.

In the embodiment shown in FIGURE l, lanes are provided to move the cutting torch at a predetermined rate longitudinally with respect to the rotation of the tube or pipe being cut although the lead screw assembly is not visible in this view.

FIGURE shows details of this portion of the mechanism, reference character 57 indicating a reversing transmission and 58, a variable speed transmission, all of which facilitate the choice of speeds for the travel of the carriage or platform.

A stepped pulley 59 is secured to the end of shaft 60 leading to the transmissions 57 and 58. A belt 61 (FIG. 1) extends around this pulley and around the tube 23 being cut so that rotation of shaft 60 is dependent upon the surface speed of travel of the pipe which in turn is governed by the belt 35 extending from the source of power.

A lead screw 62 is journalled within bearings 63 mounted upon the structure 47 and a relatively small gear 64 is secured to one end of this lead screw. A relatively large gear 65 is secured to the portion 66 of shaft 60 and engages small gear 64 thus rotating the lead screw 62.

A lead screw nut 67 is engaged around the lead screw 62 and in turn is secured to the cutter platform 48 which is slidable within the cutter platform guides 68.

By correct selection of the pulley 59, the table or platform 68 can move to effect a predetermined angle cut. It will beappreciated that the diameter of pipe being worked upon does not affect the relationship as the belt surface speed will be similar with the pipe surface speed which in turn is controllable through the source of power and associated reduction gearing.

VWhen making square or right angle cuts in pipes or tubing, a relatively small variety of speeds is all that is required but whenA cutting angles of less than 90, the torch will travel longitudinally as well as passing through relative motion between the pipe and torch. l

As a result, when cutting an angle around 45 the pipe surface speed should be reduced considerably.

It is necessary to select the proper travel speed in inches per minutes for the various metal thicknesses being cut and it is therefore necessary to prepare a chart from which the operator of the machine can predetermine his metal thickness and torch travel, taking int'o account the angle from perpendicular, if any.

Inasmuch as the motion of the rotating pipe acts as the driving member of the pulley 59, a pulley calculated for any size of pipe and for any angle will cut the same angle on all pipe sizes. A

As an example, if 221/2 degree cut on 10 inch diameter pipe was required, the distance to be cut back, by trigonometry is 4.142 inches (the function is a tangent of 221/2 which is .4142 and the'cutl back depth is 10 inches). If we assume a lead screw of threads per inch, the lead 4 screw 62 would have to turn 41.42 revolutions. If the ratio of the large gear 65 and the small gear 64 is 17.1, the large gear 65 would have to turn revolutions.

In cutting a mitre on a pipe, a line scribed through the axis of the pipe passing through the perimeter at a point where the cut is begun would form a line symmetry. In other words, one half would be the same at the other half.

It therefore follows that the operation of making a mitre would be to form a complete operation while the pipe turns half way around (through 180) and then to reverse the motion `to perform a similar operation starting at the opposite side.

With the aforementioned 10 inch diameter pipe, length of pipe surface in 180 equals equals 15.708 inches.

Therefore the large gear must turn 2.436 revolutions in 15 .708 inches of belt travel.

Therefore the circumference of pulley 59 will be equals 6.4-48 inches.

Therefore the diameter will be 2.052 inches.

If the same calculations are worked for example, for a 3 inch pipe and a 22%. degree angle, it will be found that the pulley diameter l59 will also be 2.052 inches.

It is of course desirable to ensure that no slippage oc curs between belt 61, pulley 59 and pipe 23 and reference to FIGURE 6 will show one method of belt tightening to reduce this slippage to the minimum.

A bearing support shaft 69 is screw threadably attached to a cross member 70 spanning the supporting framework and is rotatable by means of hand crank 71. A belt en= gaging pulley 72 is secured to the opposite sidey of this bearing shaft 69 and engages one run 73 of the belt 61 thus applying tension thereto. j A v In order to maintain the tube 23 upon the wheels 22, a further belt 74 may extend aroundthe pipe 23 and around a belt pulley 75 carried in an adjustable bracket 76 s C that downward pressure can be exerted upon the pipe 23;

FIGURES 5 and 7 show the preferred' embodiment which deals principally with the rotation of the feed screw by means of a direct gear drive.

The pipe 23 is rotated by means of the belt 35 as here-j inbefore described although this portion is not illustrated in FIGURE 5. The drive pulley 34 is shown however and belt 35 extends around the pulley and around the pipe 23.

From the drive shaft 34, a gear train assembly 77 is provided and consists of 'bevel gear 78 `on shaft 34 ens gaging bevel gear 79 secured to one end of shaft `80 and being supported within bearings 81. This shaft inclines upwardly and is provided with a further bevel gear 81 upon the other end thereof which in turn engages a bevel gear 82 secured to a line shaft 83 journalled between bearings 84 and 85 lon the supporting structure and below the cutting torch assembly collectively designated 15.

Two sets of pulleys 86 are provided one upon each side of the central bearing upon the line sha-ft 83 and these pulleys are adjustable along the line shaft as desired.

A belt 87 (FIG. 7) extends around one of these pulleys and around pulley 59 secured to the shaft 60 as hereinbefore described thus providing more positive `drive between the source of power and the lead screw 62.

In this connection, belt tightening pulley 88 is provided to maintain the correct tension of belt 87 If it is desirable to eliminate belt 87, then a gear train 89 may be incorporated between the line shaft 83 and the lead screw 62, such a gear train being illustrated in FIGURE 8 which incorporates a conventional 4reversing mechanism operable by handle 90. However, if this type of gear train is used it will be appreciated that extremely accurate control of the speed of rotation of the source .of power is required.

Under these circumstances the diameter of pulley 34" assumes considerable importance. As mentioned previously, the size of the pipe 23 being cut does not affect the size of pulley required for a predetermined angle cut. Therefore a calculation is required in order to select the correct pulley which is to be Iused on shaft 34' and this pulley will have to be turned accurately as to the diameter thereof.

With this arrangement, the pipe .surface speed is directly proportioned to the feed screw speed and the very slight slippage which might obtain between the Ibelt and the pipe in any one revolution would 'be tolerable.

The variable speed transmission 57 shown in the drawings, is required so that in the case of a relatively small angle cut of approximately 5, for example, the feed is relatively slow which would require a pulley 59 of relatively large diameter. By contrast, if an angle of 60 were being cut, then the feed is much faster requiring a relatively small dia-meter pulley.

Inasmuch as the ability of a belt to grip a pulley is proportional to the size of a pulley and inasmuch as, in this application, a very minimum amount of slippage can be tolerated, it is necessary to use pulley 59 which provides sufficient friction.

If a 6 inch diameter lpulley (for example) is required to provide sufficient lfriction means must be provided for increasing the feed speed other than reducing the pulley size and the variable speed transmission 57 is desirable under these circumstances.

Since various modifications can be made in my invention as hereinabove described, and many apparently widely different embodiments of same made within the spirit and scope of the claims witho-ut departing from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.

What I claim as my invention is:

1. A pipe cutting machine comprising in combination a longitudinally extending supporting framework, means for supporting a length of pipe for rotation thereon, means to rotate said pipe, means on one end of said Iframework for eliminating endwise movement of said rotating pipe, and a cutting torch assembly adjustably positioned on said framework, said means to rotate said pipe comprising a source of power in said framework, and a drive belt extending from said source of power, and around said pipe, said means for eliminating endwise movement of said pipe comprising in conjunction with said drive belt, a transverse roller journalled for rotation across said supporting framework and adjacent one end thereof, said transverse roller being adjustable within limits upwardly and downwardly and adapted to contact said -rotating pipe, one side of said belt passing over said transverse roller and rotating same in a direction to urge said pipe towards one end of said supporting framework, a vertically adjustable thrust roller secured to said one end, the perimeter of said thrust roller being engageable with the adjacent end of said pipe.

2. The device according to claim 1 in which said means for supporting said length of pipe comprises a pair of longitudinally exten-ding rails forming part of said supporting framework, a plurality of cradles spanning said rails and adjustable therealon-g, each of said cradles including an arcuate upper surface and pair of guide wheels journalled for rotation within said upper surface, said guide wheels being adjustable across said arcuate surface.

3. The device according to claim 1 which includes means on said :framework for moving said cutting torch assembly lengthwise as said pipe rotates.

4. The device according to claim 3 in which said means comprises a longitudinally extending guide assembly secured to said framework and parallel therewith, -said cutting torch assembly being slidably mounted for adjustment along said guide assembly, a pair of torch platform guides mounted on said guide assembly, a torch platform mounted for sliding movement on said platform guides, a lead screw assembly journalled for rotation on said platform guides, a lead Iscrew nut engaging said lead screw and being secured to said torch platform, means operatively connecting said lead screw for rotation to said source of power and means for reversing the direction of rotation of said lead screw.

5. The device according to claim 4 in which said means operatively connecting said lead screw for rotation to Isaid source of power includes a pulley on one end of sai-d lead screw and a belt extending around said pulley and said n pipe whereby rotation of said pipe causes rotation of said lead screw and hence movement of said -torch platform.

46. The device according to claim 4 in which said means operatively connecting said lead screw for rotation to said source of power comprises a line shaft journalled for rotation in said supporting framework and parallel to said longitudinal guide assembly, a gear train connected between vsaid source of power and said line shaft, at least one pulley assembly on said line shaft, a pulley on one end 4of said lead screw, and a 'belt extending around said liar; screw pulley and said pulley assembly on said line s a t.

References Cited bythe Examiner UNITED STATES PATENTS 2,077,277 4/1937 Smith 266-23 2,656,050 10/1953 Best et al 214-340 l 2,680,607 6/ 1954 Hollinger 266-23 3,090,513 5/1963 Handwerk et al. 214-340 ,FOREIGN PATENTS 557,116 ll/l963 Great Britain.

JOHN F. CAMPBELL, Primary Examiner.

L. J. WESTFALL, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTION Patent No. 3,300,201 January 24, 1967 Robert F. Atkinson It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the heading to the printed specification, lines 4 and d." read Associated Plumbing 5, for "Plumbing Heating Lt Heating Ltd.

Signed and sealed this 14th day of November 1967.

(SEAL) Attest:

EDWARD I. BRENNE] Edward M. Fletcher, I r. Attesti'ng Officer Commissioner of Patents 

1. A PIPE CUTTING MACHINE COMPRISING IN COMBINATION A LONGITUDINALLY EXTENDING SUPPORTING FRAMEWORK, MEANS FOR SUPPORTING A LENGTH OF PIPE FOR ROTATION THEREON, MEANS TO ROTATE SAID PIPE, MEANS ON ONE END OF SAID FRAMEWORK FOR ELIMINATING ENDWISE MOVEMENT OF SAID ROTATING PIPE, AND A CUTTING TORCH ASSEMBLY ADJUSTABLY POSITIONED ON SAID FRAMEWORK, SAID MEANS TO ROTATE SAID PIPE COMPRISING A SOURCE OF POWER IN SAID FRAMEWORK, AND A DRIVE BELT EXTENDING FROM SAID SOURCE OF POWER, AND AROUND SAID PIPE, SAID MEANS FOR ELIMINATING ENDWISE MOVEMENT OF SAID PIPE COMPRISING IN CONJUNCTION WITH SAID DRIVE BELT, A TRANSVERSE ROLLER JOURNALLED FOR ROTATION ACROSS SAID SUPPORTING FRAMEWORK AND ADJACENT ONE END THEREOF, SAID TRANSVERSE ROLLER BEING ADJUSTABLE WITHIN LIMITS UPWARDLY AND DOWNWARDLY AND ADAPTED TO CONTACT SAID ROTATING PIPE, ONE SIDE OF SAID BELT PASSING OVER SAID TRANSVERSE ROLLER AND ROTATING SAME IN A DIRECTION TO URGE SAID PIPE TOWARDS ONE END OF SAID SUPPORTING FRAMEWORK, A VERTICALLY ADJUSTABLE THRUST ROLLER SECURED TO SAID ONE END, THE PERIMETER OF SAID THRUST ROLLER BEING ENGAGEABLE WITH THE ADJACENT END OF SAID PIPE. 